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World Journal of Clinical Cases 2025年第3期13卷 42-49页

作者： Na Li Yue-Yue Ren Ying Tang Qi Yang Tian-Tian Meng Song Li jing zhang Stomatological Hospital and College Anhui Medical UniversityHefei 230032Anhui ProvinceChina Department of Endodontics The Affiliated Stomatological Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and teenagers, but the maintenance of pulphealth and the calcific healing of multiple root fractures are rarely reported in *** SUMMARY This case reports healing of a permanent tooth with complicated crown–root andadditional root fractures, in which pulp health was maintained. A 10-year-old girlfell and fractured the root of her maxillary left central incisor at the cervical *** the coronal fragment was repositioned, the tooth was splinted until thetooth was no longer mobile, 2 years later. Eight years after treatment, the toothhas remained asymptomatic with vital pulp and localized gingival ***-beam computed tomography revealed not only calcified healing of the CRFbut also spontaneous healing in an additional undiagnosed root fracture. Thefracture line on the enamel could not be healed by hard tissue and formed agroove in the cervical crown. It was speculated that the groove was related to thelocalized gingival *** This case provides a clinical perspective of the treatment of a tooth with acomplicated CRF and an additional root fracture.

关键词： Complicated crown-root fracture Multiple root fracture Spontaneous healing Cone-beam computed tomography Long-term follow-up Case report

Priori information analysis of optocoupler accelerated degradation experiment based on failure mechanism verification test

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Defence Technology（防务技术） 2020年第2期16卷 392-400页

作者： Xuan-gong zhang Xi-hui Mu jing Feng hui-zhi Li Department of Ammunition Engineering Army Engineering University Shijiazhuang CampusShijiazhuang050000China Hunan Ginkgo Data Technology Co. Ltd.Luositang RoadChangshaHunan410100China

The optocoupler is a weak link in the inertial navigation platform of a kind of guided *** is necessary to use accelerated storage test to verify the storage life of long storage *** for small sample products,it is very important to obtain prior information for the design and implementation of accelerated degradation *** this paper,the optocoupler failure mechanism verification test is designed and the experimental results are analyzed and the prior information is *** results show that optocouplers have two failure modes,one is sudden failure and the other is degradation failure;the maximum temperature stress of optocoupler can’t exceed 140℃;the increase of leakage current of optocoupler is caused by movable ions contaminating the LED *** surface leakage current is proportional to the adsorption *** increase of leakage current makes p-n junction tunneling effect occur which LEDs the failure of the *** lifetime distribution model of the optocoupler is determined by the failure *** lifetime of the optocoupler is subject to the lognormal *** degeneracy orbit of the optocoupler leakage current is described by a power law *** estimated values of the orbital parameters are initially calculated and the parameters of its life distribution function are *** above information lays a good foundation for the optimization design and data processing of the accelerated degradation experiment.

关键词： Priori information Failure mechanism Failure mechanism verification test Accelerated degradation

WELL TESTING ANALYSIS FOR HORIZONTAL WELL WITH CONSIDERATION OF THRESHOLD PRESSURE GRADIENT IN TIGHT GAS RESERVOIRS

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Journal of Hydrodynamics 2012年第4期24卷 561-568页

作者： GUO jing-jing zhang Su zhang Lie-hui QING Hairuo LIU Qi-guo State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500 China Central Sichuan Mining District PetroChina Southwest Oil and Gas Field Company Suining 629000 China Department of Geology University of Regina Regina SK S4S 0A2 Canada

A fundamental solution for homogeneous reservoir in infinite space is derived by using the point source function with the consideration of the threshold pressure gradient. The fundamental solution of the continuous point source function is then derived based on the Green function. Various boundary conditions of the reservoirs are considered for this case and the corresponding solutions are obtained through the mirror image reflection and the principle of superimposition. The line source solution is obtained by integration. Subsequently, the horizontal-well bottom hole pressure response function for a non-linear gas flow in the homogeneous gas reservoir is obtained, and the response curve of the dimensionless bottom hole pressure and the derivative for a horizontal well in the homogeneous gas reservoir are obtained. In the end, the sensitivities of the relevant parameters are analyzed, The well test model presented in this paper can be used as the basis of the horizontal well test analysis for tight gas reservoirs.

关键词： horizontal well non-linear gas flow threshold pressure gradient tight gas reservoir

The effect of impeller slot jet on centrifugal pump performance

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Journal of Hydrodynamics 2019年第4期31卷 733-739页

作者： Ren-hui zhang Li-chen Yun jing Li School of Energy and Power Engineering Lanzhou University of Technology Lanzhou 730050China China Key Laboratory of Fluid Machinery and Systems Lanzhou University of Technology Lanzhou 730050 China

To improve the cavitation performance of the centrifugal pump, a new kind of centrifugal pump impeller with slot is proposed. The slot is on the impeller shroud near the suction side of the blade leading edge. So, the fluid with high energy in the impeller front side chamber is drained to the lowest pressure area. The jet flow would compensate the blade inlet flow with a certain energy. With numerical simulations, the pump's inner flows for 5 different slot sizes and their hydraulic performances are compared with those of the prototype pump. The slot jet would result in the increase of the impeller flow rate and the volute area ratio, leading to the head decrease within the whole flow rate range. The slot jet can suppress the reverse flow remarkably at a low flow rate, and the pump efficiency is improved. The slot jet improves the pump cavitation performance effectively, especially at a low flow rate. To some extent, the smaller the slot size is, the better the pump cavitation performance is. The cavitation performance of the slot impeller with a size of 2 mmx 1.75 mm is much better than that of the prototype impeller. Compared with the prototype impeller, the lowest pressure near the slot impeller blade inlet and even the pressure in all forepart regions are improved significantly. The slot impeller is shown to be effective in suppressing the cavitation, and the available net positive suction head is improved.

关键词： Centrifugal pump slot impeller slot jet cavitation performance circulation flow

Effects of the width and thickness of slabs on broadening in continuous casting

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 723-728页

作者： Jian-xun Fu jing-she Li hui zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China National Engineering Research Center of Continuous Casting Technology Central Iron and Steel Research Institute Beijing 100081 China

A 3D viscoelastic-plastic thermal-mechanical coupled finite element model was built on the basis of the secondary development of the commercial software ***. Numerical simulations were performed to study slab broadening in the secondary cooling zone. The effects of slab width and thickness on slab broadening were considered. The obtained results reveal that the width broadening is noticeable, and the ratio of ultimate broadening slightly increases with the increase of slab width. This agrees well with the measured data in practice. There is no obvious increase in ultimate broadening when the thickness of slabs increases.

关键词： continuous casting slabs broadening finite element method

FPGA implementation of 500-MHz high-count-rate high-time-resolution real-time digital neutron-gamma discrimination for fast liquid detectors

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Nuclear Science and Techniques 2024年第8期35卷 101-113页

作者： hui‑Yin Shen jing‑Long zhang Jie zhang Jian‑Hang Zhou College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Southwestern Institute of Physics P.O.Box 432Chengdu 610041China

Fast neutron flux measurements with high count rates and high time resolution have important applications in equipment such as *** this study,real-time neutron and gamma discrimination was implemented on a self-developed 500-Msps,12-bit digitizer,and the neutron and gamma spectra were calculated directly on an FPGA.A fast neutron flux measurement system with BC-501A and EJ-309 liquid scintillator detectors was developed and a fast neutron measurement experiment was successfully performed on the HL-2 M tokamak at the Southwestern Institute of Physics,*** experimental results demonstrated that the system obtained the neutron and gamma spectra with a time accuracy of 1 *** count rates of up to 1 Mcps,the figure of merit was greater than 1.05 for energies between 50 keV and 2.8 MeV.

关键词： Neutron-gamma discrimination Liquid scintillation detector Real-time spectrum analyzer

Weak-force sensing with squeezed optomechanics

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Science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 71-81页

作者： Wen Zhao Sheng-Dian zhang Adam Miranowicz hui jing Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China College of Physics and Materials Science Henan Normal UniversityXinxiang 453007China Faculty of Physics Adam Mickiewicz UniversityPozna´n 61-614Poland

We investigate quantum-squeezing-enhanced weak-force sensing via a nonlinear optomechanical resonator containing a movable mechanical mirror and an optical parametric amplifier(OPA). Herein, we determined that tuning the OPA parameters can considerably suppress quantum noise and substantially enhance force sensitivity, enabling the device to extensively surpass the standard quantum limit. This indicates that under realistic experimental conditions, we can achieve ultrahigh-precision quantum force sensing by harnessing nonlinear optomechanical devices.

关键词： weak-force sensing squeezing optomechanics

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： jing-jing Guo Kai-Xiang Di Lie-hui zhang Yu-Long Zhao hui-Ying Tang Rui-Han zhang Ye Tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

Numerical investigation of particle deposition on converging slot-hole film-cooled wall

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Journal of Central South University 2017年第12期24卷 2819-2828页

作者： ZHOU Jun-hui zhang jing-zhou College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016 China Jiangsu Province Key Laboratory of Aerospace Power System Nanjing 210016 China

Numerical research on the dilute particles movement and deposition characteristics in the vicinity of converging slot-hole(console) was carried out, and the effect of hole shape on the particle deposition characteristics was investigated. The EI-Batsh deposition model was used to predict the particle deposition characteristics. The results show that the console hole has an obvious advantage in reducing particle deposition in comparison with cylindrical hole, especially under higher blowing ratio. The coolant jet from console holes can cover the wall well. Furthermore, the rotation direction of vortices near console hole is contrary to that near cylindrical hole. For console holes, particle deposition mainly takes place in the upstream area of the holes.

关键词： gas–solid flow particle deposition film-cooled wall converging slot film cooling hole numerical simulation

健康儿童318例冠状动脉内径超声心动图测定结果分析

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实用儿科临床杂志 2011年第23期26卷 1813-1815页

作者：徐阳孙景辉张金鑫朴金花吉林大学白求恩第一医院小儿心血管科

目的测量吉林省健康儿童超声心动图的冠状动脉内径正常值,并探讨其影响因素。方法选择2010年5-12月在吉林大学白求恩第一医院就诊的14岁以下健康儿童318例,并按年龄分为6个组,18 d～组、1岁～组、3岁～组、6岁～组、9岁～组、12～14岁... 详细信息

目的测量吉林省健康儿童超声心动图的冠状动脉内径正常值,并探讨其影响因素。方法选择2010年5-12月在吉林大学白求恩第一医院就诊的14岁以下健康儿童318例,并按年龄分为6个组,18 d～组、1岁～组、3岁～组、6岁～组、9岁～组、12～14岁组。测量各组儿童身高、体质量、收缩压、舒张压。采用TOSHIBA SSH-880CV型多普勒超声诊断仪测定其左冠状动脉(LCA)、右冠状动脉(RCA)和主动脉根部(AO)内径。根据身高、体质量求得体表面积,并计算LCA/AO和RCA/AO值。采用SPSS17.0进行统计学分析。结果各年龄组LCA与RCA均值比较差异均有统计学意义(Pa<0.05)。各年龄组组间LCA和RCA均值比较差异亦有统计学意义(F=84.347、88.885,Pa=0.000)。LCA/AO值与RCA/AO值在各年龄组间差异均无统计学意义(F=0.112、0.717,P=0.990、0.611)。Logistic一元线性回归分析结果显示LCA、RCA内径值与年龄、身高、体质量、体表面积、收缩压均呈正相关,对以上相关因素进行Logistic多元线性回归分析,结果显示年龄、体表面积与冠状动脉内径相关性最强。结论冠状动脉内径与AO内径的比值是判断冠状动脉扩张的理想指标,对指导临床工作有重要作用。

关键词：超声心动图冠状动脉正常值